Suppliers of many products and services employ high volume direct mail advertising. Such mass mailings may include personalized information on the envelope alone or on the envelope and on inserts within the envelope. Inclusion of personalized information on the inserts requires coordination of the printing and stuffing of the envelopes to ensure that the inserts are stuffed within the correct envelope.
The stuffed envelopes should also have the appearance, to the greatest extent possible, of correspondence individually and manually prepared for the addressee and should avoid the appearance of mere "junk mail". One way to avoid the "junk mail" appearance is for the envelope to substantially appear to be a regular mail envelope. Such envelopes are normally identified by the generally triangular closure flaps.
Automated systems for stuffing pre-formed envelopes require complex mechanism, for example, air streams, to open the envelopes for receiving the inserts. However, such mechanisms are not efficient and are relatively complex.
Other systems make and fold an envelope around an insert. For example, U.S. Pat. No. 4,312,169 to Golicz et al. discloses a system in which the envelope and insert are formed from the same web with individual or personal information printed on the portions forming both the envelope and the insert. After the insert and the envelope are separated, the insert is folded and the folded insert is placed on the rear face of the front panel of the envelope. The insert is fed in a direction parallel to the longitudinal or longest dimension of the envelope, as the envelope moves on a conveyor in a direction perpendicular to the envelope longitudinal direction. Once the insert is located on the envelope front panel, the envelope back panel is folded over the insert. Subsequently, a closure flap is folded over to seal the envelope. Adhesive is applied to seal the envelope. Additional inserts can be added sequentially.
U.S. Pat. No. 4,205,504 to Gregoire et al also discloses making and stuffing envelopes from a continuous web. Glue strips are printed on the web by a glue applicator. The envelope is formed by folding. After the envelope is formed, inserts are inserted through the open top of the envelope in a direction transverse to the longitudinal direction of the envelope. After one or more inserts are added, the envelope closure flap is glued and folded over by a plow folder to seal the envelope. Individual stuffed envelopes are separated by a shears along the side glue lines of the envelope.
Other envelope stuffing systems are disclosed in U.S. Pat. Nos. 5,115,973 to Hipco et al, 4,668,212 to Kotani, 4,912,999 to Stenner and 5,233,812 to Coppola. However, none of these prior systems form the envelopes and stuff the inserts into the envelopes in a single pass to provide a simple yet effective mechanism for forming stuffed envelopes.